docs: def normal_h3(size: int = 10000) -> HistogramND:
      """A simple 3D histogram with normal distribution.
  
      Parameters
      ----------
      size : Number of points
      """
      data1 = np.random.normal(0, 1, (size,))
      data2 = np.random.normal(0, 1, (size,))
      data3 = np.random.normal(0, 1, (size,))
      return h3([data1, data2, data3], name="normal", axis_names=tuple("xyz"), title="3D normal distribution")